Contact Label Error Please help!

My phone has recently started acting unusual. Out of no where the other day all of the labels for my phone's contacts have what sort of looks like HTML codes around it. (ex. _$!<mobile>!$_) I doesn't seem to effect my phone preformance although it has been running slower. I have no clue what the problem is and I don't know where to start to get it fixed.

Also I have never downloaded anything to my phone outside of Itunes this is why I am confused as to how my phone could mess up.